Alumina has some outstanding advantages such as good corrosion resistance, so that it has been widely developed and applied. But the toughness of a conventional alumina ceramic may be relatively poor.
In the related art, zirconium oxide was added into the alumina ceramic so as to improve the toughness of the alumina ceramic, and by adding zirconium oxide, the toughness may reach a range of 5 MPam1/2 to 6 MPam1/2. Chinese patent application CN02111742 discloses a zirconia toughened alumina (ZTA) ceramic, which contains 60 wt % of zirconium oxide whose content is even larger than that of alumina, thus that the outstanding advantages of alumina itself maybe disappeared. In this condition, the cost of the alumina ceramic may be increased and alumina specific properties may be influenced or even disappear.